Correlation between irradiation conditions and nanoparticles obtained in case of laser ablation of aluminum targets in liquids

Abstract

The process of nanoparticles production by nanosecond pulsed laser ablation of aluminum targets situated in deionized water was studied from the point of view of laser–target interaction and incident laser fluence domain selection as a preliminary stage in the process of nanoparticles production. We have analyzed the irradiated surface morphology and crater profiles as a function of irradiation conditions (incident fluence and irradiation pulses number) by optical microscopy and white light interferometry in order to determine the most efficient coupling between the irradiation conditions and the irradiated surface immersed in liquid. The obtained nanoparticles were studied “in situ”, as obtained in suspension in water and “ex situ”, using TEM. TEM analyses have demonstrated that we have obtained nanoparticles with the lowest dimensions of 3–5 nm organized in clouds with dimensions between 40 and 80 nm. Typically the obtained nanoparticles presented two clear distributions, one corresponding to low diameters in the 6–10 or 20–40 nm regions, and another with a distribution around a maximum situated at hundreds of nanometers (250–290 nm). The obtained nanoparticles distribution was correlated with the irradiation conditions.